September 24, 2026
Sadegh Karimi

Sadegh Karimi

Academic Rank: Associate professor
Address: Department of Chemistry, Faculty of Nano, Bioscience and Technology
Degree: Ph.D in Chemistry
Phone: 07731222074
Faculty: Faculty of Nano and Biotechnology

Research

Title
Fabrication and Optimization of Melanin/PDA-Modified MXene Interlayered Polyamide TFN Membranes for Brackish Water Desalination
Type Thesis
Keywords
Desalination, Reverse Osmosis, Thin‑Film Nanocomposite Membrane, MXene, Interfacial Polymerization
Researchers zahra sadeghi zadeh (Student) , Sadegh Karimi (First primary advisor) , Seyed Abdollatif Hashemifard (Second primary advisor)

Abstract

Water scarcity and drought represent critical challenges to the survival of life on Earth. Membrane-based desalination technology, particularly reverse osmosis (RO) using thin- film composite (TFC) membranes, offers an efficient solution for freshwater production. Despite significant advancements, this technology still faces limitations such as relatively low water permeability and the inherent permeability–selectivity trade-off, which restrict its overall performance. To address these limitations, the incorporation of nanoparticles into TFC membranes resulting in thin-film nanocomposite (TFN) membranes has led to improved desalination efficiency and performance. MXenes, a class of two-dimensional nanomaterials, possess high specific surface area, strong surface functionalization capability, suitable mechanical stability, and significant hydrophilicity. Therefore, they are considered promising candidates for enhancing the performance of polyamide thin-film membranes containing nanosheets. In this study, a polyethersulfone (PES) polymeric support layer was first prepared as the membrane substrate. Subsequently, MXene nanosheets modified with melanin nanoparticles and a polydopamine (PDA) coating layer were employed as an interlayer. Following this, a polyamide active layer was fabricated via interfacial polymerization on top of the interlayer. At each stage, optimal conditions were determined to maximize water flux and salt rejection. The prepared membranes were characterized using various analytical techniques, including FTIR, zeta potential analysis, DLS, SEM, elemental mapping, XRD, and contact angle measurements. Finally, the membrane performance was evaluated in a laboratory-scale reverse osmosis system using parameters such as pure water flux and salt rejection. For the optimized iTFN membrane, the pure water flux was measured as 4.21 ± 0.28 L. m⁻².h⁻¹. bar⁻¹, and the NaCl (1000 ppm) rejection reached 93.3 ± 1.3%. Furthermore, the membrane exhibited a Na₂SO₄ (1